Albion captain Gordon Greer has been warned he faces a fight to win his place back.
The centre-half returned from a calf injury in last Saturday's FA Cup victory over Reading.
Boss Oscar Garcia has to decide whether to restore Greer to his Championship line-up for Birmingham's visit tomorrow or stick with Adam El-Abd.
Oscar'a assistant Nathan Jones said: "There is competition all throughout the squad, everyone. Look at the goalkeepers? Two goalkeepers have played (Tomasz Kuszczak and Peter Brezovan), Casper Ankergren was outstanding in his last game for the development squad.
"Bruno will be back (in contention) this week. Stephen's Ward's got competition - we've got competition right throughout the squad.
"With all the injuries we had earlier in the season all we asked was that we get our team back. We're not far off that now."
El-Abd, meanwhile, has revealed Oscar's summer arrival came in the nick of time to cement his Albion future, with Barnsley interested in signing him.
The long-serving defender said: "With all the uncertainty at the club at the time, the chairman and the Board took time to appoint Oscar so in that time there was no manager. It was all up in the air.
"It was kind of getting to a stage where I had to possibly look after my family, because I couldn't afford to be out of contract. My future here was unclear but as soon as Oscar came in everything was sorted in a matter of days."